Heat exchange member and method of making



Oct. 8, 1940- E. .1, HoUDRY HEAT EXCHANGE MEMBER AND METHOD OF MAKING Filed July 23, 1937 mvENToR E ugeNE LHD udrg ATTORNEY roten-ted oct. s, 1940 lUNITED STATES PATENT oFFicE 'HEAT EXCHANGE RIEMBER AND METHOD F MAKING Application July 23, 1937, Serial No. 155,186

Claims.

'I'he present invention relates to finned tubes or conduits and to a method of making or constructing the same. More particularly the invention concerns the use of fins on tubes or con- 5' duits, as hereinafter illustrated and described, and to a method of assembling the iins on and attaching them to tubes. The fins primarily contemplated may be referredto as transverse fins.

It is an object of this invention to provide a y method for rapidly making or fabricating conduits with transverse or similar ns attached thereto. A further object is to employ nn members which are of such structure that they are particularly adaptable for use in my method of 145v assembly. -One aspect of my invention involves shaping the iins so that portions or flanges thereof provide for uniform or any desired spacing of fins. These and other objects and advantages will be' apparent from the description taken as a The problem of making tubes having transverse fins attached thereto, and doing so rapidly and cheaply, is one of considerable commercial 2 is a perspective view of -a tube or conduit having a series ot fins of different shape thereon and in the course of being attached thereto; and

vIilg. 3 is a longitudinal sectional view taken on 35- line I-I of Fig. 2.

Theiins. such as'n 2 shown inFig. l ornns 2a shown in Figs. 2 and 3. may be formed from plates of any desired'thickness cut in desired shapes (e. g., square or round) which are ceno trally punched and then drawn; expanded or otherwise processed to provide a flange (continuous or broken) which will fit the tube to which the tins are to be attached. The plates may be slotted from the periphery -of each to points adja- 45 cent the central opening to produce fins which are generally segmental in character. This may 4 duit,` nn members of square, round or other desired peripheral contour are forced over or slid o VVonto'me.rimessa positioned with the slots in the several fins in straight or curved alignment.

5s (In the event that the ilns are slotted after being mounted on the tube, the slots will be made in alignment.) As illustrated in Fig. 2 I a plurality of rows of slots 3amay be provided, four rows being indicated. The ns may be held in desired spaced relation by flanges, such as upturned 5 ange Il on iin member 2 or flanges la shown in Figs. 2 and `3, or they may be spacedby collars of suitable length which surround the tube and are disconnected from' the fin members. -Notches or the like may be provided on successiveiins, if lo desired, to insure the maintenance .of proper alignment of slots sa during welding, although this is generally unnecessary. Welding electrode 8 (Fig. 2), shown in broken away view, is in the "course of being moved lengthwise of the t`ube through one row of slots, thus simply and quickly to weld the iins 2a to the tube I; note the welding bead 1. In place of the welding, electrode shown. any other desired type of welding tool may be employed. It is optional whether the welding head is maintained stationary land the tube is moved therealong so that the welding tool passes through the aligned slots,- or vice versa, whether the tube is maintained stationary and the welding tool is moved. Also. welding tools may be passed through any plurality or all of slots simultaneously, if desired. and this'is sometimes advantageous in the production of a finished tlnned tube which is free from warpage.

The plates or iins are preferably slotted deeply enough so that tno nn mem wm be nuxeo with 3 the metal of the tube during the welding operation. Where the ilange I of the n n is suiliciently thin no slottm'g at ou ormenange wnlbenes-- sary in order to weld the ange to the tube but, when it is thicker, the aange my be partially slotted, as illustrated in-Fig. 1 by the partial slots 4 which beginwhere the full slots I end. The radial slots may be cut entirely through the plate, including the flange, in whichcase the sections of the plates or ons wm be held in place 0 by a press or other suitable means while being welded to the tube. 'Howeven when cutting the radial slots (such as slots l in Fig. l or la in Fig.

2), it is preferable to make the cut only part-way 45 through the Bange, so that the flange will hold the fin plate in place and the n metal at this point will be fluxed with the metal of the tubeduring .the welding operation. Inasmuch as the flange on each plate, when employed, provides a m good bearing surface on the tube and maygripv the same with alight press fit, tack or'spot welding of flanges is suiilcient formany uses. On the other hand, the flanges may be used only as spacer members, not welded to the tube, conduction between the tube and iin being established by welding the iln to the tube at the inner ends of the slots, such as of slots 3 and 3a shown in the drawing.

Where desired, the fianges of the ilns may be welded to the tube at points intermediate the slots by making a step rotation oi' either the welding head or the tube assembly as the welding head advances in relation to the tube. The step rotation may, for example, be of 30, 45 or 60 degrees, more or less.

In addition to fins of the particular types illustrated in the drawing, it will be understood that my invention is applicable in the case of other ns which extend around or substantially around a tube or conduit whether they are rectangular, round or of other peripheral contour and whether, in a plane perpendicular to the length of the tube, they are generally fiat, curved. etc., so long as my above-described method of joining fins to a tube is applicable. f

The uses for which nned tubes as described may be employed are many and varied. They may be used where there is a fluid inside the tube and a solid material surrounding the tube, or vice versa, or where there are iluids both within and around the tube, or where there are solids both within and around the tube, where it is desired to eect the exchange of heat between points within the tube and points exterior thereto. For example, by way of speeic illustration, finned tubes or conduits constructedas herein illustrated may be employed in controlling the temperatures of catalytic beds or masses, e. g., in apparatus such as shown in Patent. No. 2,078,947, issued to myself on May 4, 1937 or in my copending application VSerial No. 84,787, filed June 12, 1936 which issued on June 27, 1939, as Patent No. 2,163,599. Again, my invention may be employed in constructing tubular nned members for various other particular uses involving heat exchange, for example those illustrated in Patents Nos. 855,239, issued to J. F. Faries on May 28, 1907, 1,920,800, issued to J. W. McCausland on August l, 1933, or 1,838,105 issued to T. E. Murray on December 29, 1931.

The tubes or conduits on which the fins are attached obviously are not limited to single-walled tubes but include other types of conduits, e. g., double or nested conduit assemblies such as shown in Patent No. 1,987,903, issued to myself on Januaryl, 1935, or conduits of the type illustrated in my\ aforementioned Patent No. 2,078,947 or my aforementioned copending application.

What I claim is:

1. In the construction of a tube with a series of transverse iins attached thereto, the steps which compris'e sliding centrally punched fins onto said tube with spacer members between adjacent fins to maintain them in desired spaced relationship, said fins having slots extending from the peripheries of the ns to points adjacent their central openings but not completely severing the fins into sections, positioning said ns with their slots ln alignment along the length of the tube, and passing a welding tool through the aligned slots so as to join said series of fins to said tube.

2. In a method of providing a tube with transverse ns, the steps o1' forming ilanged apertures in metal plates, providing slots in each plate from the periphery to points adjacent the aperture and grooves' in the outer wall of each flange in line with the slots, positioning the plates on the tubethrough the apertures and spacing the plates by means of the aperture flanges, aligning the slots of each plate and Joining the plates to 'the tube by fusing the grooved areas of the flanges to the tube.

3. In a method of providing a metal tube with transverse fins, the steps of forming a flanged aperture in metal plates, slotting each plate inwardly from the outer edge to provide a plurality of interconnected segments, positioning the segmented plates on the tube in spaced relation and aligning the slots, joining the tube and segmented plates by passing a welding tool through the aligned slots between adjacent segments of each plate and fusing the tube and segments at the Joining line.

4. Inthe construction of a metallic core with transverse fins, the steps of forming an aperture in a plurality of plates, slotting each plate from its periphery to points adjacent the aperture presenting segments interconnected by a continuous web portion, positioning the plates on the core in spaced relation and aligning the slots of the plates, and securing the plates by fusing the web portion with the core.

5. A finned heat exchange device adapted f emcient heat transfer comprising a conduit for conveying fluid, apertured plates extending transversely of the conduit, each plate having the apertures provided with spacing flanges and slots outwardly thereof. said slots extending from the outer edge of the plate to said flange forming segments of extensive heat exchange surface, and a welded joint between the segments for securing each plate integrally to the conduit with the slots in alignment. l

EUGENE J. HOUDRY. 

